Brother MFC620CN Service Manual page 408

Selector
No.
1 Dial tone/busy tone detection
| level during recording of ICM
3 (Not used.)
4
| Not used.
8
NOTE: Selectors 1 through 3 are applicable to models equipped with internal TADs.
Selectors 1 through 3:
If the machine (called station) detects dial tone (400 Hz continuously) or busy tone (400 Hz
intermittently) exceeding the detection level specified by these selectors for the period specified by
selectors 1 through 4 of WSW35, then it interprets the calling station as being disconnected. The
machine stops TAD recording and disconnects the line.
WSW30
(Function setting 8)
Function
Dial tone/busy tone detection level during recording of ICM (Not used.)
App. 4-33
Setting and Specifications
No. 1 2 3
0 0 0 : -38.0 dBm (A)
0 0 1 : -39.5 dBm (B)
0 1 0 : -41.0 dBm (C)
0 1 1 : -42.5 dBm (D)
1 0 0 : -44.0 dBm (E)
1 0 1 : -45.5 dBm (F)
1 1 0 : -47.0 dBm (G)
1 1 1 : -48.5 dBm (H)
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